Size at Sexual Maturity of the Bluntnose Stingray (Hypanus say) and the Atlantic Stingray (Hypanus sabinus) from the Indian River Lagoon, Florida

Size at Sexual Maturity of the Bluntnose Stingray (Hypanus say) and the Atlantic Stingray (Hypanus sabinus) from the Indian River Lagoon, Florida

Alvin Sherman Library

Bluntnose (Hypanus say) and Atlantic (Hypanus sabinus) stingrays in Family Dasyatidae are benthic species found in abundant numbers in the Indian River Lagoon, a major estuarine ecosystem along the Atlantic coast of Florida. Although the Indian River Lagoon ecosystem is experiencing increasing anthropogenic pressures and effects on local habitats from climate change, data specifically regarding H. say and H. sabinus life histories are currently lacking. Using specimens collected monthly from a collaboration with the Florida Fish and Wildlife Conservation Commission, average size at sexual maturity was assessed for both sexes of H. say (n = 126) and H. sabinus (n = 133). Size for each stingray was determined using multiple weight and length measurements including disk width. Maturity was determined by calcification of the claspers and development stage of testes for males and the development stage of ovaries for females. Previous size at maturity studies on other dasyatid stingray species reported that females generally tend to reach maturity at a larger size then males. The results from this study will provide a better understanding of the life histories for these two stingray species and assist with the development of Florida state agency management policies for these populations in the Indian River Lagoon.